diff --git a/20210202/es-20210202.tex b/20210202/es-20210202.tex
index d400d29a33abb7bbfdd9a7b72f802e193bb3f669..03e2ecc08238402500f3459ea9cc2f743595ff9d 100644
--- a/20210202/es-20210202.tex
+++ b/20210202/es-20210202.tex
@@ -20,7 +20,7 @@
 % Attribution-ShareAlike 3.0 Unported License along with this
 % document.  If not, see <http://creativecommons.org/licenses/>.
 
-% README: Verschlüsselung
+% README: Verschlüsselung: Grundlagen
 
 \documentclass[10pt,t]{beamer}
 
diff --git a/20210209/es-20210209.tex b/20210209/es-20210209.tex
index 638ad0ca94086c2a795476a726d0774f36ad700d..6e0dc6dad83aeba8b17cde05d3c1db2c2912ef96 100644
--- a/20210209/es-20210209.tex
+++ b/20210209/es-20210209.tex
@@ -20,7 +20,7 @@
 % Attribution-ShareAlike 3.0 Unported License along with this
 % document.  If not, see <http://creativecommons.org/licenses/>.
 
-% README: Verschlüsselung
+% README: Verschlüsselung: Zertifizierung
 
 \documentclass[10pt,t]{beamer}
 
diff --git a/README.md b/README.md
index a97dadd7f472764de3d0214b257051328d3e1333..a18ec2c49de4ec85f32a6e9ec4aff345bf64eed9 100644
--- a/README.md
+++ b/README.md
@@ -29,8 +29,8 @@ Vortragsfolien:
  * [12.01.2021: Echtzeit: Multitasking, Ressourcen](https://gitlab.cvh-server.de/pgerwinski/es/raw/2020ws/20210112/es-20210112.pdf)
  * [19.01.2021: Multitasking: Scheduling, Echtzeit: Prioritäten](https://gitlab.cvh-server.de/pgerwinski/es/raw/2020ws/20210119/es-20210119.pdf)
  * [26.01.2021: Threads](https://gitlab.cvh-server.de/pgerwinski/es/raw/2020ws/20210126/es-20210126.pdf)
- * [02.02.2021: Verschlüsselung](https://gitlab.cvh-server.de/pgerwinski/es/raw/2020ws/20210202/es-20210202.pdf)
- * [09.02.2021: Verschlüsselung](https://gitlab.cvh-server.de/pgerwinski/es/raw/2020ws/20210209/es-20210209.pdf)
+ * [02.02.2021: Verschlüsselung: Grundlagen](https://gitlab.cvh-server.de/pgerwinski/es/raw/2020ws/20210202/es-20210202.pdf)
+ * [09.02.2021: Verschlüsselung: Zertifizierung](https://gitlab.cvh-server.de/pgerwinski/es/raw/2020ws/20210209/es-20210209.pdf)
  * [alle in 1 Datei](https://gitlab.cvh-server.de/pgerwinski/es/raw/2020ws/es-slides-2020ws.pdf)
 
 Fotos:
diff --git a/es-slides-2020ws.pdf b/es-slides-2020ws.pdf
index 1e72147e01af478d4395dfcc1eda73bc7c8519a7..8ec0cff0581fcf93f0467b0e481b8577fab919d4 100644
Binary files a/es-slides-2020ws.pdf and b/es-slides-2020ws.pdf differ